1. Field of the Invention
The present invention relates to bladder assembly and more particularly to such a bladder assembly having inside air cushion and a method of manufacturing same.
2. Description of Related Art
Conventionally, a waterbed or air bed can be used as a bed, mattress, etc. For waterbed, a number of drawbacks have been found. For example, many waterbeds have been constructed with a flat upper surface formed of a single sheet of vinyl. This single sheet tended to conform closely to the body of a user so that it sometimes became difficult for the user's skin to breathe. Perspiration often resulted. Further, since water is a fairly good heat conductor, a heater is typically required to keep water in the bed at a suitably high temperature compatible with the needs of a human body. Furthermore, most waterbeds can be adjusted in firmness by adjusting the amount of water in the bed bladder. But this firmness is the same throughout the bed. Moreover, transportation of a folded waterbed is still not easy due to its bulkiness.
For air bed, despite advantages of being lightweight and easy transportation, the first one of the above drawbacks still exists. Hence, a need for improvement exists.